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Re: [debug-early] C++: emit early debug info for all globals, not just statics


On 10/02/2014 02:21 PM, Aldy Hernandez wrote:
Actually, I think we/I need to rethink this whole globals thing.
Currently we're early dumping global *_DECLs, and hoping dwarf2out
recursion will also pick up types and any derivatives from the *_DECLs,
but taking a closer look I've noticed a lot of things are not being
dumped early.

For instance:


     foo()
     {
       typedef int ITYPE;
       ITYPE var = 5;
     }

For the above code, var's DIE gets outputted _after_ the compilation
proper has been run here:

   if (! declaration && outer_scope && TREE_CODE (outer_scope) !=
ERROR_MARK
       && (!DECL_STRUCT_FUNCTION (decl)
       || DECL_STRUCT_FUNCTION (decl)->gimple_df))
     ...
     ...
     decls_for_scope (outer_scope, subr_die, 0);

I think we should be outputting DIEs for locals at the end of parsing,
so my patch going through level->names IMO is wrong.  We should be
dumping all *_DECLs created by the FE, not just globally scoped ones.

The way to dump locals is by recursion. If the current process isn't hitting these, that's a bug, but I don't think it means we need to fundamentally change the approach. Why aren't we hitting that decls_for_scope when we early dump foo?

Another example currently not being dumped early is...

     function()
     {
       class Local {
       public:
         void loc_foo (void) { }
       };

       Local l;
       l.loc_foo ();
     }

...since loc_foo() is not in level->names.

Again, dumping function() should imply dumping Local and its members.

Jason


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